Skip to content

AtlasEngine: Fix out-of-bounds row access in PaintCursor (#20269) #20363

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
yuu61 wants to merge 1 commit into from
+7 −1
Closed

AtlasEngine: Fix out-of-bounds row access in PaintCursor (#20269) #20363

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
8 changes: 7 additions & 1 deletion src/renderer/atlas/AtlasEngine.cpp
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -620,7 +620,13 @@ try
const auto cursorWidth = 1 + (options.fIsDoubleWidth & (options.cursorType != CursorType::VerticalBar));
const auto top = options.coordCursor.y;
const auto bottom = top + 1;
const auto shift = gsl::narrow_cast<u8>(_p.rows[top]->lineRendition != LineRendition::SingleWidth);
// coordCursor is relative to the renderer's viewport, which can momentarily
// disagree with our own viewport (the size of _p.rows) when the viewport
// dimensions change. Clamp the row index just like the other Paint*() methods
// before indexing into _p.rows; if the cursor really is outside the viewport,
// cursorRect collapses to empty below and nothing is drawn.
const auto row = gsl::narrow_cast<u16>(clamp<til::CoordType>(top, 0, _p.s->viewportCellCount.y - 1));
const auto shift = gsl::narrow_cast<u8>(_p.rows[row]->lineRendition != LineRendition::SingleWidth);
auto left = options.coordCursor.x - (_api.viewportOffset.x >> shift);
auto right = left + cursorWidth;

Expand Down
Loading